This bulb is a 600 watt METAL HALIDE CONVERSION bulb and can only be used with systems that have a 600 watt HIGH PRESSURE SODIUM (HPS) ballast. All you have to do is SIMPLY SCREW THE BULB INTO YOUR 600w HPS SYSTEM! No switches, no special ballasts - simply screw the bulb into your existing systems mogul based socket. Note: You cannot use this bulb with any other wattage High Pressure Sodium system (250 watt, 400 watt, 1,000 watt etc) nor can it be used with any other type of H.I.D. lighting ballasts (Metal Halide, Mercury Vapor). This bulb is for use with only the 600 watt High Pressure Sodium type ballast.

Why do I need a specialty Metal Halide (MH) Conversion bulb?

Do you want to grow the best plants possible? You should make the most of your 600w HPS grow light system by using this bulb. Growing plants vegetatively under an HPS bulb makes them stretch and become leggy. When you use this Metal Halide Conversion bulb your plants will grow bushier, greener and better than you could with a High Pressure Sodium bulb. Then when it's time to flower/bloom/bud your plants, simply screw the 600w HPS bulb in for excellent result in that stage of plant growth.

How long does this MH Conversion light bulb last?

This 600w Metal Halide Conversion bulbs have a rated life of 20,000 hours. One year is 8,760 hours. It is, however, suggested that people using Metal Halide (MH) bulbs for growing plants should replace their bulb after about 12 months of use. This ensures your bulb is emitting the maximum amount of light it can before the lamp begins to degrade and emit less light.

Does this bulb come with a warranty?

YES, this GrowBright 600 watt Metal Halide Conversion bulb comes with a 1 YEAR WARRANTY. We stand behind our products 100% and will replace your bulb if it burns out within one year of the purchase date. You can count on us to be there for you during and after the sale. We work hard to keep all our customers happy, please check out our thousands of +feedback responses and you'll see why we are the best!